When the endgame arrived QPR politely ushered themselves out with barely a flicker of resistance. There was no arguing at the door, no recriminations or any real sense that they expected anything else. The worst team in the Premier League fetched their coat, left the premises and it was not particularly easy to imagine they might be back any time soon.

QPR look a good fit for the Championship if they can fold this meekly and did anyone really believe that Clint Hill, Bobby Zamora and Karl Henry were the men to keep them in the top division?

“He was here when we were shit,” the home fans sang about Richard Dunne, one-time Manchester City captain and prolific own-goal connoisseur. They meant it affectionately but, in another sense, it says something that the man assigned to subduing Sergio Agüero once went by the nickname of Honey Monster on this patch, back in the days when the wind howled and the curtains trembled.

That particular battle was predictably one-sided as the Argentinian’s hat-trick moved him to 31 goals for the season, his best total at City despite his recurring injury issues. QPR’s wage bill in the last few years has been higher at times than that of Atlético Madrid and Borussia Dortmund, both recent Champions League finalists – and not far off the entire total of Major League Soccer. Yet their lack of stardust is staggering and, if anything, it was just a surprise City did not turn their superiority into an even more emphatic scoreline.

For that, QPR were indebted to Rob Green’s goalkeeping, particularly in the second half when some of his colleagues hoisted the white flag. Green was exposed more times than he will want to remember but managed to emerge with some credit despite the frequency with which the ball was in his net. Unfortunately for QPR it was something close to chaos in front of him. Just consider the second goal as one example, as City broke from defending a corner, David Silva played the ball forward and Yun Suk-young let it go under his foot for Agüero to run clear. It was not the mistake that was incredible; it was the fact that QPR’s left-winger was their only man back.

Agüero had opened the scoring inside four minutes and Manuel Pellegrini’s team played with so much authority that it was hard to comprehend how their title challenge had faltered so badly after the turn of the year. An allowance has to be made for the moderate standard of opposition – “no club this year has played against us this way,” Pellegrini said – but this was the crisp, stylish football that makes City a joy to watch on the good days.

Video: Chris Ramsey admitted QPR were ‘nowhere near’ Premier League quality against Manchester City, after a 6-0 defeat saw his team relegated.

Agüero was rampant. Silva was at the hub of everything and QPR were a rabble. At the final whistle Junior Hoilett could hardly wait to get off the pitch. At least his team-mates did bother to go over to the away end to thank them for travelling.

Agüero’s first goal was the culmination of a diagonal run, right to left, into the penalty area, eluding Hill first and then Matt Phillips before clipping his shot over Green.

Aleksandar Kolarov made it 2-0 with a free-kick from nearly 30 yards out and then it was just a question of how ruthless City were feeling and the scale of the away side’s capitulation. At one point Joey Barton, supposedly the heart and soul of this QPR team, gave the ball away with a sloppy pass from the wing and then simply stood in the manager’s technical area as play went on. By that stage Agüero had completed his hat-trick, firing the ball to Green’s right after Phillips had brought down Silva for a penalty that might have warranted a red card and more ignominy.

Six minutes later Kolarov swung in a corner. The substitute Wilfried Bony headed on and Agüero slid the ball across the six-yard area to leave James Milner with a tap-in. It was simple, brutal stuff, even discounting the many occasions when City could feasibly have taken the scoring into new territory.

Bony struck the post with a shot of his own before playing in Silva to take the ball round Green and finish the scoring five minutes before the end.

Shortly beforehand Shaun Wright-Phillips had come on to cheers from City’s fans, remembering the player of old, and abuse from the away end, knowing him for what he is now: a symbol of the club’s excesses, making a fortune out of almost nothing.

Chris Ramsey at least brought a shred of dignity to the occasion with his post-match thoughts but the QPR head coach could not argue with Barton’s assertion that they had been undermined by “bad eggs” in the dressing room. Wright-Phillips was not one, he insisted, but the allegation was fair. “We have players who could have helped us who haven’t helped us.”

Ramsey was being generous when he tried to say his players had not given up but his own performance was considerably more impressive than his players and what a farce that QPR discovered on Friday that Sandro could not play because his visa had expired and nobody had apparently realised.